Getting along with two roommates, especially a couple, can be tricky. Does each person pay 1/3 of the utilities? Who gets the parking? Is the new person always out voted? IMo, it's not the price, it's the situation.
We are a FIRE couple. We recently converted part of our home into a Junior ADU. The tenant has a separate entrance, 1bedroom, a private bath, mini kitchen, house kitchen privileges, laundry access, and ample parking. We charge a similar rent, with utilities included. We're in the Bay Area, so similar housing costs.
In your situation, I'd incentiveize your tenants to find someone they'd be comfortable living with.